The present invention relates to small, pocket-held butane lighters for cigarettes and the like, and more particularly, is directed to a butane lighter having a mechanism for preventing unintentional and accidental activation.
Many conventional push-button butane lighters use a piezoelectric ignition system. In such a system, the user depresses a push-button which is maintained in a reciprocable position. Depression of the push-button initiates a gas flow and simultaneously activates the piezoelectric ignition system to produce a spark in an area to which the gas is fed. The spark thus generated causes ignition of the gas, which continues as long as the user depresses the push-button to supply the gas.
However, such a piezoelectric butane lighter is susceptible to misuse by children who are able to activate the lighter relatively easily. Additionally, such piezoelectric lighters could accidentally be ignited in the purse or pocket of the owner by some other object therein pressing against the push-button to a sufficient extent to activate the piezoelectric ignition system.
Accordingly, it is desirable to develop a butane lighter having a piezoelectric ignition system, which can be disabled or made inactive, thereby preventing such accidental or unintentional ignition. At the same time, this objective must be achieved without hampering a user's ability to intentionally unlock and activate the lighter with a minimum of difficulty, that is, typically with one hand and with as little manipulation as is necessary.
U.S. Pat. No. 4,921,420 to Johnston discloses a child-resistant, disposable lighter having a grind wheel and flint type of ignition system, and which provides a means for preventing operation of the actuation lever. Although the lighter disclosed by Johnston may be difficult for children to operate, and may even deter accidental ignition, it is also relatively difficult for an adult to intentionally activate the device. Further, the lighter is relatively complex in construction due to the additional means, thereby adding substantially to the cost thereof.
U.S. Pat. No. 4,904,180 to Nitta discloses a gas lighter equipped with a locking means to prevent undesired ignition. The locking means generally comprises a U-shaped stopper which is slidably fitted to the top of a thumb-pusher by fitting its inside ridges in corresponding notches made on the three sides of the thumb pusher. A hook-shaped leaf spring biases the stopper so that the thumb-pusher may not be depressed without first sliding the stopper in a first direction. The thumb-pusher may then be depressed, thereby activating the piezoelectric element. When the thumb pusher is released, it automatically springs back, and the leaf spring pushes the stopper back. However, this lighter may still be easily activated by a child. Further, the locking mechanism may not be easily deactivated by the user, since the stopper must be pushed each time until it has reached the unlocked position.
U.S. Pat. No. 4,859,172 to Nitta discloses a piezoelectric lighter equipped with a rotatable hook-shaped safety lock which includes a pivot which can snap-fittingly be received into a circular hole of the casing to prevent actuation of the push-cap. However, this safety lock has an external mechanism which suffers from the disadvantage that foreign objects in a handbag or pocket may dislodge the lock and allow unintentional activation of the lighter. Additionally, this mechanism can be relatively easily manipulated by children. Moreover, engagement of this lock mechanism is accomplished by an action that requires manipulation at a different location on the lighter than the actual ignition thereat by the reciprocable movement of the push cap.
U.S. Pat. No. 4,487,570 to Lowenthal discloses a butane lighter having a piezoelectric ignition system wherein downward operative movement of an actuator slide causes pivoting of a member to create a flame aperture, thus revealing the nozzle of the burner valve and allowing gas to be discharged. Continued downward movement of the actuator slide operates the piezoelectric ignition system for igniting the gas released by the start of the downward motion. However, this lighter has no security lock mechanism, thereby permitting children the opportunity to tamper therewith.
U.S. Pat. No. 4,179,260 to Lowenthal provides a lighter having a piezoelectric ignition system. The lighter is provided with a lid and the actuation member of the piezoelectric ignition system is inaccessible as long as the lid is closed. The most relevant aspect of this invention is the embodiment of FIGS. 13-18 in which the depressible actuating member is pivoted about a hinge. A compression spring acts on a portion of the actuating member below the hinge in order to urge the serrated part of the actuating member down into the confines of the casing. When the lid is open, the lid causes a cam member to swing upward and ride over a surface of the actuating member, causing it to pivot against the action of the spring and so as to provide accessibility for application of the operator's thumb. Although this embodiment discloses a pivoting actuating member, it is very complicated since it requires a spring to normally bias the actuating member to its closed or inoperative position and a cam mechanism with a lid to move the actuator to its operative position. However, no provision is made to prevent a child from opening the cover, and upon opening the cover, from actuating the piezoelectric ignition system by simply depressing the actuating button. Additionally, it is still possible that the lid of the butane lighter could be opened while inside a pocketbook, thereby exposing the actuating member to possible depression by some other object therein.
U.S. Pat. No. 3,898,031 to Rusakowicz discloses a gas fueled safety lighter. The safety feature of this lighter relates to a head assembly which can be moved out of the way to permit the gas to escape. However, this lighter is not designed for use with a piezoelectric ignition system and the safety mechanism cannot be disabled when desired.
U.S. Pat. No. 3,466,134 to Rabe discloses a lighter having an actuating member which is movable between an inactive or inoperative position and an active or operative position when depressed. The actuating member is coupled through a linkage to the cap member so as to pivot the cap member open above the gas exit port when the actuating number is depressed. However, there is no provision for an actual locking mechanism nor is there any teaching of how this cover mechanism may be adapted for use with the piezoelectric ignition system in a lighter.
Therefore, there exists a need for the development of a lighter using a piezoelectric ignition system and having a mechanism for preventing the accidental actuation of the ignition system in a pocket or purse. Additionally, the disengaging mechanism should prevent operation of the lighter by children.